1. Field of Invention
This invention relates to wedges, specifically to mechanized wedges utilized primarily for splitting wood.
2. Discussion of Prior Art
Heretofore, when using a wedge to split a log, one introduced the cutting edge of the wedge into the log by manually holding the wedge perpendicular to the surface to be entered, and using a sledge hammer or similar item in the other hand, "starting"(driving the wedge far enough into the log to be self-supporting) the wedge. Once the wedge had been properly "started", one continued to hammer on the wedge, using the force developed by the hammer to propel the wedge deeper and deeper into the wood until ultimately the log would split apart.
This technique has several shortcomings. Specifically, starting the wedge by holding it with one hand and using an unwieldy sledge (usually 8 to 12 lbs.) in the other, attempt to hit the wedge with enough force and at a proper angle to cause the wedge to enter the wood and remain stable. Obviously this technique requires both hands to move simultaneously, but at different rates, and ultimately in different directions. The hand equipped with the sledge moves rapidly toward the wedge and, upon impact, slows dramatically while it attempts to drive the wedge forward, then recoils to dissipate the energy not consumed by the wedge. The other hand is attempting to maintain stability and positioning of the wedge prior to impact, guide and stabilize the wedge upon impact, and protect itself from harm should the sledge be slightly or grossly misdirected. A slight misdirection of the sledge can result in misalignment and/or incomplete insertion. Gross misdirection can result in serious injury. Unfortunately, this injury can be severe because of the effort, or force, necessary to "start" a wedge of conventional design and construction. Significant "force" is necessary because the traditional wedge must be "started" by driving the entire length of the cutting edge into the wood. Obviously, this "force" is a function of among other things the angle, width and length of the cutting edge, as well as the density, moisture, overall length and stability of the log to be penetrated. Anything less than ideal conditions and accomplished skill results in a wedge that only partially enters the wood (dangerously springing out upon a future, more forceful impact), or enters the wood at anything other than a perpendicular angle (which would dangerously deflect a full force sledge blow toward an adjacent object or worse yet the operator), or bounces out of the wood leaving the operator to control a reeling sledge in one hand while simultaneously trying to avoid the ricocheting, sharpened wedge.
Prior Art has recognized the inadequacies of current practices and in U.S. Pat. No. 4,295,506 to Nicholson, Oct. 20, 1981 attempted to deal with the situation by adding a short, fixed starting point to the center of the cutting edge of the wedge in hopes of minimizing the problem. Unfortunately, this technique, though a fairly inexpensive addition to the typical wedge, also has several inherent shortcomings. First, the starting point is formed of the same material and we would assume at the same time as the wedge itself. Being integral to the forged body of the wedge, as this point is worn or should it become damaged, the wedge has been reduced to the capability and susceptibility of its ancestors. Additionally, the Nicholson design provides an opportunity for injury should the operator inadvertently allow a finger to rest within the standoff that exists between the top of the log and the cutting edge of the wedge prior to the first "starting" blow. Should this happen, the blow from the sledge would cause the finger to be jammed between the sharpened, cutting edge of the wedge and the top surface of the log. Serious injury could result.